Conventionally, there has been known an approaching vehicle detection apparatus that detects a vehicle approaching an own vehicle. For example, Patent Literatures 1 and 2 below disclose a technique of detecting an approaching vehicle and calculating the approaching direction of the approaching vehicle based on a sound signal detected by a plurality of microphones of an own vehicle. Further, Patent Literature 3 below discloses a technique of using a microphone installed in a different place in response to a vehicle speed of an own vehicle when an approaching vehicle is detected and the approaching direction thereof is detected. Further, Patent Literature 4 below discloses a drive assist technique of detecting the other vehicle existing in an area serving as a blind angle with respect to an own vehicle in an intersection point or the like and notifying the existence of the approaching vehicle to a driver when the other vehicle is a vehicle approaching the own vehicle.